The present invention relates to a process of producing an acrylic ester compound that is a polymerizable monomer useful for producing photoresists of vacuum ultraviolet region.
As typical examples of esterification, there have been known (a) a dehydration and condensation reaction between an alcohol and a carboxylic acid (see page 471 of a book, Jikken Kagaku Koza 19 “Syntheses of Organic Compounds” written in Japanese and published in 1957 by Maruzen Co.), (b) a transesterification reaction between an alcohol and a carboxylic ester (see page 478 of this book), and (c) a condensation reaction between an alcohol and a carboxylic halide in a basic condition (see page 476 of this book). In general, dehydration reactions and transesterification reactions are equilibrium reactions. Therefore, it is possible to achieve a high yield by using an alcohol in an excessive amount relative to that of a carboxylic acid or carboxylic ester. These two reactions, however, are not suitable for a large-scale production in case that the alcohol is complicated in structure and high in price.
On the other hand, the above condensation reaction proceeds even if the starting materials are reacted in a molar ratio of 1:1. Therefore, this reaction can be used for a large-scale production, even if the alcohol is high in price. This reaction, however, produces an acid (HX). Thus, it is generally known to trap this acid by adding an amine to the reaction system. This addition produces an amine halide salt, which must be removed by filtration and acid washing. Thus, the condensation reaction makes the operation cumbersome.